mineral

Amethyst Quartz

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous/glassy, Crystal structure: Hexagonal (trigonal), Cleavage: None (conchoidal fracture)

Identified May 31, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous/glassy, Crystal structure: Hexagonal (trigonal), Cleavage: None (conchoidal fracture)

Formation & geological history

Forms in hydrothermal veins or geodes within volcanic rock, typically through the deposition of silica-rich fluids containing traces of iron that are later irradiated.

Uses & applications

Mainly used in jewelry, as decorative display pieces, and in the metaphysical or healing crystal community.

Geological facts

The purple color is caused by natural irradiation or iron impurities. It was once considered as valuable as diamonds until large deposits were found in Brazil.

Field identification & locations

Check for its hexagonal crystal habit and its ability to scratch glass but not topazes. Commonly found in Brazil, Uruguay, and South Africa.

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